All year, SNL viewers have had one burning question on their minds. And tonight, we finally got an answer: So that is what Chris Kattan looks like now.

Oh, also: Kristen Wiig really is exiting the show. I hate to see her go, but loved watching her leave – that concluding sendoff sketch might have been the sweetest thing on Saturday Night Live since Steve Martin said goodbye to Gilda Radner.

But I’m getting ahead of myself. The Kristen Wiig Farewell Tour kicked off with a Lawrence Welk Show reprise that gave Wiig’s tiny-handed Dooneese one last time to shine (at least, until Wiig returns as a guest host). Though this sketch has been well and trulyruninto the ground since its first appearance in 2008, Wiig’s commitment always makes it work – and last night, she got an extra boost from surprise guest Jon Hamm as suave Italian crooner Gionni Prosciutto (a clever tweak on Jon Hamm’s John Ham). Watching these two make beautiful music together almost makes me wish their characters in Bridesmaids could have worked things out. Not watch this video? Now you’re just being fusilli:

The episode that followed alternated between Wiig showpieces and segments that shone a spotlight on Mick Jagger, the night’s strutting guest host. These two motifs came together in the first post-monologue sketch, which is hopefully the last time Secret Word will ever grace Studio 8H. This one-joke bit wore out its welcome immediately, and I’ve never understood why it recurred so often or appeared so early in any given episode. If the writers want to let Wiig use her old-fashioned movie star voice, why didn’t they just write more “don’t make me sing” sketches? In any case: Wiig did her Mindy Elise Grayson thing, and Jagger played not-s0-closeted star Chaz Bragman. As the New York Post once wrote, “The only way it could be called a hit is if you put an ‘s’ before the ‘h.’”

The night’s biggest surprise: Jimmy Fallon didn’t make a cameo during the following sketch, a goofy bit in which Fred Armisen and Bobby Moynihan both did their best Jagger impressions. But a different SNL vet did stop by for the night’s winning Digital Short – a sequel to “Lazy Sunday,” the online sensation that effectively made YouTube what it is today. Andy Samberg was once again joined by Chris Parnell – who had been conspicuously absent from last week’s 100th Digital Short celebration – for an afternoon of innocuous entertainment set to a driving beat. Even if it couldn’t measure up to the original, “Lazy Sunday 2” featured plenty of memorable lines and moments. I especially loved the That’s So Raven shout out and this short’s answer to “Lazy Sunday“ ‘s Aaron Burr joke: “We take more shots in the theater than John Wilkes Booth!”

The episode’s one real political sketch – a segment of Politics Nation, starring Kenan Thompson’s blustering Al Sharpton – was immediately eclipsed by Jagger’s first musical performance. The ageless rocker took the stage with Arcade Fire for a lively rendition of the Stones’ “The Last Time” – an appropriate choice for an episode so concerned with nostalgia. After watching Jagger tear it up with Win Butler and co., the answer to an old meme’s question is obvious: Arcade Fire is the band that killed it with a Rolling Stone last night. If there’s any justice, this won’t be the last time they perform together.

Every time Bill Hader’s Stefon shows up on Weekend Update, I’m simultaneously elated and worried that his quirky club recommendations might start to wear thin. Thankfully, Stefon’s number isn’t up quite yet. From Brrrrr!, a club that’s “written and directed by James L. Brooks,” to Scampy, a spot featuring “a special workshop where you can build a bear, but not the kind you think,” this bizarre pixie’s weirdly specific jokes always land – and Hader’s inability to keep it together while delivering them is still more fun than it has any right to be. Sadly, we now have to survive an entire summer without Stefon; guess I’ll just eat poison ‘til I die.

The show’s post-Update sketches were generally weak. Hader’s smirking Dave Matthews impression (“I’m Dave Matthews. Remember me, from college?”) and the visual punch of Jagger dressed as his onetime Celebrity Deathmatch opponent Steven Tyler were the only highlights of a fake music festival reality show. Meanwhile, a reprise of “The Californians” gave us more delightful accents and a quick Steve Martin cameo, but failed to build on its predecessor.

But these sketches were sort of beside the point. Thanks to two additional performances by Jagger and friends, the rest of last night’s SNL felt more like a concert than a comedy show – which isn’t a bad thing, considering how good the music was. Jagger’s Foo Fighters-assisted medley of “19th Nervous Breakdown” and “It’s Only Rock ‘n’ Roll (But I Like It)” was more successful than “Tea Party,” the bluesy original number he performed with guitar virtuoso Jeff Beck – mostly because it wasn’t clear whether “Tea Party” was supposed to be funny. But both songs had their moments, proving once more that Jagger isn’t slowing down as he creeps toward his 70s.

And then came Wiig’s emotional farewell, which used a loose graduation premise to send her off in style. As Arcade Fire played “She’s a Rainbow,” Wiig danced with each of her cast mates in turn and tried to hold back tears. She seemed particularly choked up when Hader and Jason Sudeikis cut in. Finally, SNL head honcho Lorne Michaels had the last dance, and the band segued into “Ruby Tuesday.” Jagger, the band, and the cast sang the wistful tune together, joined by a few SNL vets – Amy Poehler! Rachel Dratch! Chris Kattan? – who had turned out to see Wiig off. Whether or not you’re Wiig’s biggest fan, it’s tough to watch this touching tribute without tearing up.

And just like that, Wiig is, we assume, gone for good. If Andy Samberg and Jason Sudeikis are leaving as well, it’s a bummer that the show didn’t bother giving them much of a goodbye; while Samberg did get in a callback to his most popular short, Sudeikis was practically invisible last night. But those are small quibbles – “She’s a Rainbow” ended Saturday Night Live’s 37th season on an extremely high note, and I don’t want to diminish its impact by complaining.

What did you think of last night’s finale – and of the season in general? Did Mick Jagger exceed your expectations? Which musical number was your favorite? And how sad are you to see Wiig go – especially if she takes Samberg and Sudeikis with her?